From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.6 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id DF522C2D0E9 for ; Sun, 29 Mar 2020 22:53:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id ACFDD2074A for ; Sun, 29 Mar 2020 22:53:58 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="YdqGJYdx" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729306AbgC2Wx6 (ORCPT ); Sun, 29 Mar 2020 18:53:58 -0400 Received: from mail-pl1-f180.google.com ([209.85.214.180]:40611 "EHLO mail-pl1-f180.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729298AbgC2Wx4 (ORCPT ); Sun, 29 Mar 2020 18:53:56 -0400 Received: by mail-pl1-f180.google.com with SMTP id h11so5967565plk.7; Sun, 29 Mar 2020 15:53:55 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=sender:from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=Dc7bfpCHmNwS83U0Bi65Mlbo33PDuzIuvIGhtQsVrd0=; b=YdqGJYdx6ltbimaooi+ttw+KqlWYx8MRmh9LOmjlj5hEyNqGFnXPnzE6lbgPXHl5bU KVCKS7oll0MA623EiQpeQ9oTpT83qEreP77rsKixWpyysfAtkKFhzxfjbBxfeYNuvtRk hMhjFzU5Gfbrr2dWyETndZ07r9aBqDrcSAJcM6KjmxUj92xIkd9aSFOJR9euXp0CD8fq eLN64nP/o+7ivOa+pcE6ol9vZsqw002MPPQNtq48IUlMPZlzzk42VmtUl/TIx2AOZl+g H5ZEugLzuxQjArKCS+tZhH9jtbUtwxG5tjl+62gxiQL80qi+3GrIFI+EjVMxNd0Sa9gt nOrQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:from:to:cc:subject:date:message-id :in-reply-to:references:mime-version:content-transfer-encoding; bh=Dc7bfpCHmNwS83U0Bi65Mlbo33PDuzIuvIGhtQsVrd0=; b=XSaUkhGchpi/PGyWeoKdRDehkUCC3zehQa7SsBjLW5USbYQrF+T2qo3B8PoY8QBDwT DMGlo2jjgdVs/LZQeV4llezKpkcp8d0pQgfKj03lbNXc4Sh/8yzdptbyGwFaa9MqxIeq SYAX908WMk0+YqpAa/xHsBw/oXYJ1AQhI9IaOQm0NdO6MLAmASQQLQ+sPxRiWrBf1zGD 3pzlzPL6wlK5JAqt98pdKea83iiEplaOxO1hPu0uXWwYKkWLwhOJ7cx+08VvZG1jXkVm /kR9RXevcUa+rHyqOVgz+nr8X+2Ljs7+n8en/jdvf/oU552BTNkBqQRvUQs+nIuT2aw1 y3tA== X-Gm-Message-State: ANhLgQ1fmOiAPO346qf2bzAmo17F6YpR0UTfE2xcoX9xVufEvX4upKTM XQ1C29itEeAVmBAE7wzEeWT4c/rD X-Google-Smtp-Source: ADFU+vtQ63VPBNTDlYfVigY4wtT/DhplItwfEqc/nd4wWXBBBOZopUALO9r6TqtlZLiOmOMF0qNc2Q== X-Received: by 2002:a17:90a:fa8f:: with SMTP id cu15mr11040487pjb.108.1585522434203; Sun, 29 Mar 2020 15:53:54 -0700 (PDT) Received: from localhost.localdomain (c-73-93-5-123.hsd1.ca.comcast.net. [73.93.5.123]) by smtp.gmail.com with ESMTPSA id i187sm8710386pfg.33.2020.03.29.15.53.52 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 29 Mar 2020 15:53:53 -0700 (PDT) From: Joe Stringer To: bpf@vger.kernel.org Cc: Lorenz Bauer , netdev@vger.kernel.org, daniel@iogearbox.net, ast@kernel.org, eric.dumazet@gmail.com, kafai@fb.com Subject: [PATCHv5 bpf-next 4/5] selftests: bpf: add test for sk_assign Date: Sun, 29 Mar 2020 15:53:41 -0700 Message-Id: <20200329225342.16317-5-joe@wand.net.nz> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200329225342.16317-1-joe@wand.net.nz> References: <20200329225342.16317-1-joe@wand.net.nz> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: bpf-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org From: Lorenz Bauer Attach a tc direct-action classifier to lo in a fresh network namespace, and rewrite all connection attempts to localhost:4321 to localhost:1234 (for port tests) and connections to unreachable IPv4/IPv6 IPs to the local socket (for address tests). Includes implementations for both TCP and UDP. Keep in mind that both client to server and server to client traffic passes the classifier. Signed-off-by: Lorenz Bauer Co-authored-by: Joe Stringer Signed-off-by: Joe Stringer Acked-by: Martin KaFai Lau --- v5: No change v4: Add acks v3: Add tests for UDP socket assign Fix switching back to original netns after test Avoid using signals to timeout connections Refactor to iterate through test cases v2: Rebase onto test_progs infrastructure v1: Initial commit --- .../selftests/bpf/prog_tests/sk_assign.c | 276 ++++++++++++++++++ .../selftests/bpf/progs/test_sk_assign.c | 143 +++++++++ 2 files changed, 419 insertions(+) create mode 100644 tools/testing/selftests/bpf/prog_tests/sk_assign.c create mode 100644 tools/testing/selftests/bpf/progs/test_sk_assign.c diff --git a/tools/testing/selftests/bpf/prog_tests/sk_assign.c b/tools/testing/selftests/bpf/prog_tests/sk_assign.c new file mode 100644 index 000000000000..25f17fe7d678 --- /dev/null +++ b/tools/testing/selftests/bpf/prog_tests/sk_assign.c @@ -0,0 +1,276 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (c) 2018 Facebook +// Copyright (c) 2019 Cloudflare +// Copyright (c) 2020 Isovalent, Inc. +/* + * Test that the socket assign program is able to redirect traffic towards a + * socket, regardless of whether the port or address destination of the traffic + * matches the port. + */ + +#define _GNU_SOURCE +#include +#include +#include +#include + +#include "test_progs.h" + +#define BIND_PORT 1234 +#define CONNECT_PORT 4321 +#define TEST_DADDR (0xC0A80203) +#define NS_SELF "/proc/self/ns/net" + +static const struct timeval timeo_sec = { .tv_sec = 3 }; +static const size_t timeo_optlen = sizeof(timeo_sec); +static int stop, duration; + +static bool +configure_stack(void) +{ + char tc_cmd[BUFSIZ]; + + /* Move to a new networking namespace */ + if (CHECK_FAIL(unshare(CLONE_NEWNET))) + return false; + + /* Configure necessary links, routes */ + if (CHECK_FAIL(system("ip link set dev lo up"))) + return false; + if (CHECK_FAIL(system("ip route add local default dev lo"))) + return false; + if (CHECK_FAIL(system("ip -6 route add local default dev lo"))) + return false; + + /* Load qdisc, BPF program */ + if (CHECK_FAIL(system("tc qdisc add dev lo clsact"))) + return false; + sprintf(tc_cmd, "%s %s %s %s", "tc filter add dev lo ingress bpf", + "direct-action object-file ./test_sk_assign.o", + "section classifier/sk_assign_test", + (env.verbosity < VERBOSE_VERY) ? " 2>/dev/null" : ""); + if (CHECK(system(tc_cmd), "BPF load failed;", + "run with -vv for more info\n")) + return false; + + return true; +} + +static int +start_server(const struct sockaddr *addr, socklen_t len, int type) +{ + int fd; + + fd = socket(addr->sa_family, type, 0); + if (CHECK_FAIL(fd == -1)) + goto out; + if (CHECK_FAIL(setsockopt(fd, SOL_SOCKET, SO_RCVTIMEO, &timeo_sec, + timeo_optlen))) + goto close_out; + if (CHECK_FAIL(bind(fd, addr, len) == -1)) + goto close_out; + if (CHECK_FAIL(listen(fd, 128) == -1)) + goto close_out; + + goto out; +close_out: + close(fd); + fd = -1; +out: + return fd; +} + +static int +connect_to_server(const struct sockaddr *addr, socklen_t len, int type) +{ + int fd = -1; + + fd = socket(addr->sa_family, type, 0); + if (CHECK_FAIL(fd == -1)) + goto out; + if (CHECK_FAIL(setsockopt(fd, SOL_SOCKET, SO_SNDTIMEO, &timeo_sec, + timeo_optlen))) + goto close_out; + if (CHECK_FAIL(connect(fd, addr, len))) + goto close_out; + + goto out; +close_out: + close(fd); + fd = -1; +out: + return fd; +} + +static in_port_t +get_port(int fd) +{ + struct sockaddr_storage ss; + socklen_t slen = sizeof(ss); + in_port_t port = 0; + + if (CHECK_FAIL(getsockname(fd, (struct sockaddr *)&ss, &slen))) + return port; + + switch (ss.ss_family) { + case AF_INET: + port = ((struct sockaddr_in *)&ss)->sin_port; + break; + case AF_INET6: + port = ((struct sockaddr_in6 *)&ss)->sin6_port; + break; + default: + CHECK(1, "Invalid address family", "%d\n", ss.ss_family); + } + return port; +} + +static int +run_test(int server_fd, const struct sockaddr *addr, socklen_t len, int type) +{ + int client = -1, srv_client = -1; + char buf[] = "testing"; + in_port_t port; + int ret = 1; + + client = connect_to_server(addr, len, type); + if (client == -1) { + perror("Cannot connect to server"); + goto out; + } + + srv_client = accept(server_fd, NULL, NULL); + if (CHECK_FAIL(srv_client == -1)) { + perror("Can't accept connection"); + goto out; + } + if (CHECK_FAIL(write(client, buf, sizeof(buf)) != sizeof(buf))) { + perror("Can't write on client"); + goto out; + } + if (CHECK_FAIL(read(srv_client, &buf, sizeof(buf)) != sizeof(buf))) { + perror("Can't read on server"); + goto out; + } + + port = get_port(srv_client); + if (CHECK_FAIL(!port)) + goto out; + if (CHECK(port != htons(CONNECT_PORT), "Expected", "port %u but got %u", + CONNECT_PORT, ntohs(port))) + goto out; + + ret = 0; +out: + close(client); + if (srv_client != server_fd) + close(srv_client); + if (ret) + WRITE_ONCE(stop, 1); + return ret; +} + +static void +prepare_addr(struct sockaddr *addr, int family, __u16 port, bool rewrite_addr) +{ + struct sockaddr_in *addr4; + struct sockaddr_in6 *addr6; + + switch (family) { + case AF_INET: + addr4 = (struct sockaddr_in *)addr; + memset(addr4, 0, sizeof(*addr4)); + addr4->sin_family = family; + addr4->sin_port = htons(port); + if (rewrite_addr) + addr4->sin_addr.s_addr = htonl(TEST_DADDR); + else + addr4->sin_addr.s_addr = htonl(INADDR_LOOPBACK); + break; + case AF_INET6: + addr6 = (struct sockaddr_in6 *)addr; + memset(addr6, 0, sizeof(*addr6)); + addr6->sin6_family = family; + addr6->sin6_port = htons(port); + addr6->sin6_addr = in6addr_loopback; + if (rewrite_addr) + addr6->sin6_addr.s6_addr32[3] = htonl(TEST_DADDR); + break; + default: + fprintf(stderr, "Invalid family %d", family); + } +} + +struct test_sk_cfg { + const char *name; + int family; + struct sockaddr *addr; + socklen_t len; + int type; + bool rewrite_addr; +}; + +#define TEST(NAME, FAMILY, TYPE, REWRITE) \ +{ \ + .name = NAME, \ + .family = FAMILY, \ + .addr = (FAMILY == AF_INET) ? (struct sockaddr *)&addr4 \ + : (struct sockaddr *)&addr6, \ + .len = (FAMILY == AF_INET) ? sizeof(addr4) : sizeof(addr6), \ + .type = TYPE, \ + .rewrite_addr = REWRITE, \ +} + +void test_sk_assign(void) +{ + struct sockaddr_in addr4; + struct sockaddr_in6 addr6; + struct test_sk_cfg tests[] = { + TEST("ipv4 tcp port redir", AF_INET, SOCK_STREAM, false), + TEST("ipv4 tcp addr redir", AF_INET, SOCK_STREAM, true), + TEST("ipv6 tcp port redir", AF_INET6, SOCK_STREAM, false), + TEST("ipv6 tcp addr redir", AF_INET6, SOCK_STREAM, true), + }; + int server = -1; + int self_net; + + self_net = open(NS_SELF, O_RDONLY); + if (CHECK_FAIL(self_net < 0)) { + perror("Unable to open "NS_SELF); + return; + } + + if (!configure_stack()) { + perror("configure_stack"); + goto cleanup; + } + + for (int i = 0; i < ARRAY_SIZE(tests) && !READ_ONCE(stop); i++) { + struct test_sk_cfg *test = &tests[i]; + const struct sockaddr *addr; + + if (!test__start_subtest(test->name)) + continue; + prepare_addr(test->addr, test->family, BIND_PORT, false); + addr = (const struct sockaddr *)test->addr; + server = start_server(addr, test->len, test->type); + if (server == -1) + goto cleanup; + + /* connect to unbound ports */ + prepare_addr(test->addr, test->family, CONNECT_PORT, + test->rewrite_addr); + if (run_test(server, addr, test->len, test->type)) + goto close; + + close(server); + server = -1; + } + +close: + close(server); +cleanup: + if (CHECK_FAIL(setns(self_net, CLONE_NEWNET))) + perror("Failed to setns("NS_SELF")"); + close(self_net); +} diff --git a/tools/testing/selftests/bpf/progs/test_sk_assign.c b/tools/testing/selftests/bpf/progs/test_sk_assign.c new file mode 100644 index 000000000000..bde8748799eb --- /dev/null +++ b/tools/testing/selftests/bpf/progs/test_sk_assign.c @@ -0,0 +1,143 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (c) 2019 Cloudflare Ltd. +// Copyright (c) 2020 Isovalent, Inc. + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +int _version SEC("version") = 1; +char _license[] SEC("license") = "GPL"; + +/* Fill 'tuple' with L3 info, and attempt to find L4. On fail, return NULL. */ +static inline struct bpf_sock_tuple * +get_tuple(struct __sk_buff *skb, bool *ipv4) +{ + void *data_end = (void *)(long)skb->data_end; + void *data = (void *)(long)skb->data; + struct bpf_sock_tuple *result; + struct ethhdr *eth; + __u64 tuple_len; + __u8 proto = 0; + __u64 ihl_len; + + eth = (struct ethhdr *)(data); + if (eth + 1 > data_end) + return NULL; + + if (eth->h_proto == bpf_htons(ETH_P_IP)) { + struct iphdr *iph = (struct iphdr *)(data + sizeof(*eth)); + + if (iph + 1 > data_end) + return NULL; + if (iph->ihl != 5) + /* Options are not supported */ + return NULL; + ihl_len = iph->ihl * 4; + proto = iph->protocol; + *ipv4 = true; + result = (struct bpf_sock_tuple *)&iph->saddr; + } else if (eth->h_proto == bpf_htons(ETH_P_IPV6)) { + struct ipv6hdr *ip6h = (struct ipv6hdr *)(data + sizeof(*eth)); + + if (ip6h + 1 > data_end) + return NULL; + ihl_len = sizeof(*ip6h); + proto = ip6h->nexthdr; + *ipv4 = false; + result = (struct bpf_sock_tuple *)&ip6h->saddr; + } else { + return (struct bpf_sock_tuple *)data; + } + + if (result + 1 > data_end || proto != IPPROTO_TCP) + return NULL; + + return result; +} + +static inline int +handle_tcp(struct __sk_buff *skb, struct bpf_sock_tuple *tuple, bool ipv4) +{ + struct bpf_sock_tuple ln = {0}; + struct bpf_sock *sk; + size_t tuple_len; + int ret; + + tuple_len = ipv4 ? sizeof(tuple->ipv4) : sizeof(tuple->ipv6); + if ((void *)tuple + tuple_len > skb->data_end) + return TC_ACT_SHOT; + + sk = bpf_skc_lookup_tcp(skb, tuple, tuple_len, BPF_F_CURRENT_NETNS, 0); + if (sk) { + if (sk->state != BPF_TCP_LISTEN) + goto assign; + bpf_sk_release(sk); + } + + if (ipv4) { + if (tuple->ipv4.dport != bpf_htons(4321)) + return TC_ACT_OK; + + ln.ipv4.daddr = bpf_htonl(0x7f000001); + ln.ipv4.dport = bpf_htons(1234); + + sk = bpf_skc_lookup_tcp(skb, &ln, sizeof(ln.ipv4), + BPF_F_CURRENT_NETNS, 0); + } else { + if (tuple->ipv6.dport != bpf_htons(4321)) + return TC_ACT_OK; + + /* Upper parts of daddr are already zero. */ + ln.ipv6.daddr[3] = bpf_htonl(0x1); + ln.ipv6.dport = bpf_htons(1234); + + sk = bpf_skc_lookup_tcp(skb, &ln, sizeof(ln.ipv6), + BPF_F_CURRENT_NETNS, 0); + } + + /* workaround: We can't do a single socket lookup here, because then + * the compiler will likely spill tuple_len to the stack. This makes it + * lose all bounds information in the verifier, which then rejects the + * call as unsafe. + */ + if (!sk) + return TC_ACT_SHOT; + + if (sk->state != BPF_TCP_LISTEN) { + bpf_sk_release(sk); + return TC_ACT_SHOT; + } + +assign: + ret = bpf_sk_assign(skb, sk, 0); + bpf_sk_release(sk); + return ret; +} + +SEC("classifier/sk_assign_test") +int bpf_sk_assign_test(struct __sk_buff *skb) +{ + struct bpf_sock_tuple *tuple, ln = {0}; + bool ipv4 = false; + int tuple_len; + int ret = 0; + + tuple = get_tuple(skb, &ipv4); + if (!tuple) + return TC_ACT_SHOT; + + ret = handle_tcp(skb, tuple, ipv4); + + return ret == 0 ? TC_ACT_OK : TC_ACT_SHOT; +} -- 2.20.1